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teddillard
24 October 2010, 0410
So look- I'm of the particularly luddite-ular opinion that there really hasn't been any significant improvement in frame performance... performance, mind you, since about 1980. Here's a shot of my '84 VF500F frame, for example:

http://sphotos.ak.fbcdn.net/hphotos-ak-snc1/hs179.snc1/6730_1212361628695_1218396040_30609368_7348777_n.j pg

It seems like the basic engineering challenges are met with a simple double-downtube construction and the mono-shock thing got figured out and solved pretty easily too. Weights are about the same, and all this tubular-Ducati cage stuff is simple engineering trying to justify itself and marketing hoo-haa.

Are modern frames, in fact, stiffer and lighter now? Has there been a significant improvement since my favorite frame ever, the Yamaha TZ350?

(In photography, for instance, there have been no technological breakthroughs in optics since about 1960. Multi-coating lenses was the last significant improvement in the '70s, yet that doesn't stop the camera companies from claiming a "breakthrough" every year... )

http://sphotos.ak.fbcdn.net/hphotos-ak-ash2/hs041.ash2/35403_1535963198532_1218396040_31516129_8183765_n. jpg

cycleguy
24 October 2010, 0859
You must be joking! Frame stiffness to weight ratio's have dramatically improved since the 1980's. The steel tube trellis frame on the Bimota pictured has a much higher stiffness to weight ratio than your VF500 frame, not to mention the modern aluminum beam frames, which are even stiffer. Granted, you will hardly notice the difference in 20 years of frame technology just riding around town at a leisurely pace, but put on some modern wide sticky tires, a stiff USD front fork and stiff swingarm and ride the bike to it's limits on the track, and that VF500 frame of yours will feel like it has a hinge in the middle of it and have all the stiffness of a wet noodle.
I'm not knocking your VF500, it was a great bike in it's day, but hardly a match for today's modern framed bikes.

chdfarl
24 October 2010, 0949
It seems people confuse geometry and structural integrity. The vf 500 was based off of the late 70s moto gp bikes like the NS 500. They were both very good frames at the time and did use tubular perimeter frames ( that may be the wrong classification ). The big leaps in chassis over the last 25 years were in materials their stiffness and geometry. The later is not in relation to strength as it is to performance. A steeper steering angle lets the bike turn quicker and there is a huge difference between bikes prior to the late 90s an any older bikes. Not only that but the weight balance front to rear of the new bikes are the mirror ( reverse ) of the older bikes. these aspects of chassis design are hard to see with an unaware eye but are there and significant.
Frame stiffness come not only from the steering neck being linked to the swingarm pivot via two parallel beams. Modern sportbike frames are built out of thick aluminum and 4130 chromoly. Both are lighter and thus are typically thicker gauge then mild steel and thus stiffer. Ducatis use chromoly round tubing engineered in a trellis. Those two things alone are enough to say those frames are stronger. Basically the engineers took the bottom cradle portion of the old frames and used 50% of that material to tie the front end to the swingarm through the engine and gusset those areas with less material and less material means less weight. So even though old frame resemble newer frames sometime there are numbers underlying factors. That said old RACE frames are pretty badass.
http://www.motorcyclespecs.co.za/bikes/Racing%20Bikes.htm
http://phildentonengineering.com/cust/prod/large/pid4.jpg

teddillard
24 October 2010, 1122
You must be joking!

Delusional, possibly, but joking? Moi? NEVER!

Thanks for setting me straight, I do like my old steel... don't get me going on bicycle frames.

jazclrint
24 October 2010, 2244
Cycle Guy took the words right out of my mouth. But, to defend Ted a little bit, when Honda replaced the Vf500F with the CBR600F it took until the F3 before they got the weight back down on par with the 500. I can see how that would be misleading.

However, all the weight is not just from the frame. Bigger diameter forks, wider wheels and tires, bigger brakes, and a bigger motor all contributed the weight. You'd have to really search the archives to compare frame weights over the years. I feel a better and fairer comparison would be to look at Honda's 1000c line of bikes. Start with the '84 VF1000F, and look at every sport bike Honda made all of the way up to the current '10 CBR1000RR. But back to the VF500F reference. It seems to me that shortly after the 500 there was a big step forward in frame design. Look specifically at the Honda Hawk, Honda VFR750, and Suzuki GSX-R750. They all came out right around '88, and had the box section aluminum frames. I got to ride my (at the time) roommate's stock Hawk at the same time I had my stock 500 running. The Hawk was a scalpel in comparison. Even in comparison to my '91 VFR, but that was probably due to the weight of the VFR as much as anything. However the Hawk's all torque motor (30hp/30 ft-lb) wasn't a match for my 500's V4 (50hp/25 ft-lb) and I would walk my roommate, even with toasted suspension. This was 2000, and two weeks later he showed up with a brand new GSX-R750 (that I promptly almost rear-ended mid-corner with my VFR). I would say that a Hawk would actually make for a better donor bike because it is so much stiffer with little to no weight penalty.

If you then fast forward 10 years and Yamaha's R1 and R6 bikes were the start (or indicative of?) of yet the another jump in chassis development, as referred to above. At that same time you start seeing engines being used as stressed members in an effort to reduce weight and maintain or increase stiffness. It got to a point that they got too stiff. Case in point is the second iteration of the CRB900RR. I believe it was that bike that was so stiff that it had poor bump compliance while leaned over in the corners in the race track environment. The next iteration had side flex designed into the chassis, I believe. The other thing that has been jumping up in just the past few years is the diameter of fork tubes. They're huge now. It's my opinion that this is driven by the rapid and steady improvement in tire and brake technology. Of course all this stuff is on a MotoGP bike years before it ever gets to street bikes.

So, yeah, the 500 is a wet noodle in comparison to the modern bikes. But it's a well balanced wet noodle. However, I wouldn't expect a retro grouch like you to understand modern aluminum and carbon fiber designs. I bet you ride with down tube shifters too. :D

Just out of curiosity, and in the interest of full disclosure, what bikes have you owned, and (separately) what bikes have you had a chance to ride, over the last 40 years of motorcycling?

teddillard
25 October 2010, 0310
bar end, yo. (steel Fuji frame, and you'll take it away from me out of my cold, dead hands...)

Let's just say I've never raced, I started out back in the beginning on trail bikes (Husky, Suzuki, Yammy, Honda, Maico, Montessa, Rickman) Ducati, (the 250/450 single models to start) Guzzi, Guozzoni, (know what that is, there sonny boy?) Triumph (Bonnie and Trophy Trail), BMW 650, 750, 900, my first build was an RD350 cafe - all '70s vintage. I bought my SRX600 in '86, new, and frankly never looked back, or ridden much else since. So yes, in full disclosure I am a luddite, as I said, rooted firmly in the steel double downtube.

This kind of feels like making a list of your old girlfriends... huh.

Oh I rode a Harley once, but I don't like to talk about it.

Thanks for the detailed information though... it's not something I've really put much effort into keeping up with, and I'm going to now have to bite my tongue next time I see that butt-ugly Ducati girder. I threw the post up pretty much expecting to be bitch-slapped into reason...

Oh, on my understanding of carbon fiber? We were working (working with, not yabbering about it on the internets) with it back in 1972, youngster... titanium too... :p

OMG, it just dawned on me I have this photo of the garage I worked in with my buddies in HS. Here you go, if you can identify more than 5 vehicles, you win a beer.

http://sphotos.ak.fbcdn.net/hphotos-ak-ash2/hs215.ash2/47826_1619598249356_1218396040_31733226_1806431_n. jpg

teddillard
25 October 2010, 0341
Oh, and an Enertia.
http://evmc2.wordpress.com/2010/07/10/brammo-enertia-vs-zero-s-part-1-spec-battle/

...kidding aside, too, there's another angle on my perspective here. After they started making bikes that could go over 120mph, and frankly weren't much fun to ride at much under 90, I sort of lost interest in performance. I love the torque of my SRX, and realized that's a hell of a lot more fun than a bike that I'm riding at about 50% of it's capability... for me. After I saw a crap-ton of kids running out, buying GPZs and Hurricanes and then turning themselves into basket cases street racing, it kind of lost it's charm. That was the 80s, for me, and motorcycling.

So maybe my old wobbly steel is good enough for me and the street, yet. :D

chdfarl
25 October 2010, 1025
Relax Ted we love you and your opinions. At least I do. The truth is that modern sport bikes are hyper HP ridiculously light gasguslers that 90% of riders never even consider tapping. I personally love the 70s cafe style. Each decade of motorcycles has its revolutionary bikes. Since the R1 sport bikes are trying to be repli racers out of the box. The funny thing is that the knowledge was there back in the day. Thats why I posted the links in my last post. They show some crazy old race bikes. That guy Phil Denton builds replica vintage race frames and they are chromoly. Chromoly is used then and today since it could be used at a thinner gauge with greater strength. Seely was a UK company that sold CB 750 frames built the same way back then and were stiffer and lighter. A few honda CR road race bikes of the 60s used the engine as a stressed member. The late 60s 305 was the only street bike that ive seen sold at least in the US. Nine out of ten times if there is a new technology it was used once way before that.
As far as the vf vs. the nt the Hawk had 41mm forks compared to the 37mm forks on the vf. The stance of the two bikes are quite different too. Id say 50% of suspension is the weight balance. Its not felt on the road unless your flogging it but if the weight isn't slightly bias to the front end the bike wont turn or brake even close to one that is. Thats a large part as to the size of modern forks. Try braking at 120 over only 100-200 feet then lean your ass off of the seat and drag your knee then twist the throttle. You'll see how weight transfer is an issue. That said fork size tire width and frame bulk is really proportional to HP and Torque. Personally I feel that the electric race bikes are over built with the use of RSVR4 chassis with 90 horse. I see that they are heavy but they are packing way too many batteries and a big part of it is to push big wheels forks and swingarms. Thats my dumbass opinion but i like transmissions too.

teddillard
25 October 2010, 1043
I'm relaxed... no worries. I just started putting it all together, partly because of the question about what I'd ridden. The irony was that, when these bikes started being offered by the big manufacturers, they were exactly what we all thought we wanted... disk brakes, tight frames, crazy horsepower, great suspension- until we saw high school kids buying them for their first bikes and killing their own dumb asses. I remember the hardest-core racer I've ever known, cut his teeth ice racing, over 6', cut like a frikkin superhero, sold his Hurricane after he had it for 6 months. Said it was too much bike for him... and if that was the case, it's too much bike for anybody.

And yes. I heart Phil Denton.

DaveAK
25 October 2010, 1055
For no good reason other than reminiscing the best handling bike I ever had was a Yamaha RD350YPVS. It had a frame too.

BaldBruce
25 October 2010, 1902
OMG, it just dawned on me I have this photo of the garage I worked in with my buddies in HS. Here you go, if you can identify more than 5 vehicles, you win a beer.



I only know three. Two cars and one bike. Does that get me 1/2 a beer? (My family drove only Bugs for years......)

cycleguy
25 October 2010, 2018
Looks like circa 1962-4, VW Beetle, 1962ish Mercedes 220, Ducati Diana bottom end sitting on bench, Suzuki T250, Montessa, and looks like maybe a Rickman Triumph based on the looks of the cylinder head.

teddillard
26 October 2010, 0323
dude. THAT is a european model Mercedes 300 SEL 6.3, '68.
http://www.fantasycars.com/sedans/column/sedans4_merc300sel.html

(the other guesses- nobody I knew called it a Diana, least in front of Robert, but yes, and yeah, sure on the veedub, but duh - lol. the rest- FAIL)

And Dave, for you:

http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs375.snc4/45818_1619589489137_1218396040_31733214_3005129_n. jpg

cycleguy
26 October 2010, 0833
1963ish Kawasaki T10 250 perhaps? Ok, 300SEL but it's no '68, more like '63

teddillard
26 October 2010, 0842
Well, first, (I was there), second, read the link- 67 was the first year for the 300SEL.

Maico- 500 or 400, can't remember exactly which, but it was a beast.

teddillard
01 March 2011, 0523
So, yeah, I'm still on frame design. What with my R5e tube-steel frame (my target build weight is under 225 lbs) , talk lately of the Norton Featherbed, the Norton Electra being the first electric to take an ICE field... I remain unconvinced that all this aluminum-channel-cad-terminator design isn't anything but high-tech marketing going for that last 2% that costs you 400% more garbage. Call me a skeptic. :D

So I see a shot of a Vincent Comet... and I take my first good look at the rear suspension. Think the "monoshock swingarm" idea started in the '80s? Think again... here's the Vincent "cantilever suspension" rear end, patented in 1927.

http://upload.wikimedia.org/wikipedia/commons/thumb/a/ab/Cantilever_motorcycle.jpg/800px-Cantilever_motorcycle.jpg

...all that's old is new again.

Just to make one point clear... really my question is this- I'll buy the points made that design has progressed and materials have improved, but what is the actual benefit? It's hard to compare specs, since the powerplants are so different now, and I guess you'd have to do some modeling or really detailed testing to get hard numbers, but so many things in technology relate back to squeezing that last 2% out of a design. Take the basic rule of Audio. After a certain point, it costs 400% more money to get 2% more performance. Can you hear it? That 2%?

So sure, the current frames are lighter... but how much? Maybe 20lbs? Out of a 400lb bike, that's not too much. And they're stiffer? How much? This I can't really even guess... And how much to these incremental improvements really contribute to faster laps?

I'll go back to my bicycle comment above... I prefer steel, because it's more comfortable for the riding I do. I've had my ass handed to me by riders on steel bikes. The "rule" that you have to ride aluminum bikes to go fast just doesn't hold up... I guess we'll see this season what a steel frame can do in the TTXGP...

podolefsky
01 March 2011, 0851
I'll go back to my bicycle comment above... I prefer steel, because it's more comfortable for the riding I do. I've had my ass handed to me by riders on steel bikes. The "rule" that you have to ride aluminum bikes to go fast just doesn't hold up... I guess we'll see this season what a steel frame can do in the TTXGP...

Whoa...dude...aluminum is so 10 years ago. If you don't have a carbon Cervelo with carbon Zipp wheels and Dura Ace Di2, just turn around and pedal your sorry ass home. Actually, scratch the Di2, that electronic shifting crap is lame...but whatever you get better be carbon. Carbon carbon carbon...

That said, I have a carbon mountain bike that I friggin love.

__Tango
01 March 2011, 0903
Whoa...dude...aluminum is so 10 years ago. If you don't have a carbon Cervelo with carbon Zipp wheels and Dura Ace Di2, just turn around and pedal your sorry ass home. Actually, scratch the Di2, that electronic shifting crap is lame...but whatever you get better be carbon. Carbon carbon carbon...

That said, I have a carbon mountain bike that I friggin love.

The Di2 isn't all crap. the auto-trim is pretty neat, and for aero setups you can have the shifters on both the aero bars and the bullhorns. And besides, the Di2 makes this thread relaivent to an elBikeo.com forum. :)

That being said, my smog maker is in the shop, so i'm gonna ride my cervelo (without the one flashpoints (which are budget zipps) to work today. :) And i love it too. :)

teddillard
01 March 2011, 0925
oh fine. I can't talk printers, but you boys can go all bicycle geek. :p.

When you get old like me, it will dawn on you that having the hottest trick setup is simply removing every last excuse >ahem< reason for getting passed by all the youngsters...

Nuts & Volts
01 March 2011, 0926
Ted I have to disagree. Aluminum is not only lighter but it can be cheaper to manufacture, no 400% increase in cost here. Casting Aluminum is a cheap and very repeatable process. With the advance of computers you can determine how well the aluminum will set and you can determine how stiff it will be without spending more than $1000 bucks on a CAD license. I would also say 20lbs out of 400lbs is no joke. 5% weight reduction can improve all aspects of a motorcycle and even a car. I do agree that you dont have to have aluminum to go fast, but it sure helps :)

I do agree that steel tubing is the amazing for custom, but it wouldnt cut it in manufacturing. Then you've got carbon, the possibilities are endless there. Lamborginhi has a new car that uses a carbon frame. I even read an article about a company that can cast carbon fiber!

teddillard
01 March 2011, 0926
Ted I have to disagree. Aluminum is not only lighter but it can be cheaper to manufacture, no 400% increase in cost here. Casting Aluminum is a cheap and very repeatable process. With the advance of computers you can determine how well the aluminum will set and you can determine how stiff it will be without spending more than $1000 bucks on a CAD license. I would also say 20lbs out of 400lbs is no joke. 5% weight reduction can improve all aspects of a motorcycle and even a car. I do agree that you dont have to have aluminum to go fast, but it sure helps :)

I do agree that steel tubing is the amazing for custom, but it wouldnt cut it in manufacturing. Then you've got carbon, the possibilities are endless there. Lamborginhi has a new car that uses a carbon frame. I even read an article about a company that can cast carbon fiber!

Good points on the manufacturing process, but that's not speaking to performance is it? (I was using the 400% example just as an illustration, more to say that what we think is a sizable difference in end result often isn't so much...) I'm going to have to disagree (or at least remain unconvinced) until shown some facts on the 5% performance yield, sorry.

Fine for the (current) manufacturing, but that's more about keeping costs down, while being able to charge the customer more. (Did you know it costs a fraction of the price of an LP to produce a CD, yet the prices were almost double at the start of the CD "revolution", and never dropped?)

Carbon... sure, again, show me the performance benefit, and in this case, for an absolutely staggering cost increase.

Nuts & Volts
01 March 2011, 0933
You heard the man, quit your bicyclin' chatter!

podolefsky
01 March 2011, 1020
I'm going to have to disagree (or at least remain unconvinced) until shown some facts on the 5% performance yield, sorry.

Consider this (for elmoto, not bicycles). If you have a 72V, 60Ah pack, let's take an extreme case where all the energy is used for acceleration and hill climbing (yay for the frictionless world of physics). A 5% reduction weight equates to gaining roughly 5% more kWh, which is like adding another cell to a 24 cell lithium pack.

But a single 60Ah cell is about $80-90. A lot less than a carbon frame...so the choice is pretty obvious. (never mind trying to find a 75.2V charger...)

But the truth is, most of the energy is used overcoming frictoin, so that 5% weight savings probably buys you almost nothing in the real world.


Carbon... sure, again, show me the performance benefit, and in this case, for an absolutely staggering cost increase.

Actually, carbon isn't that expensive any more. You can find a very nice full carbon road bike for under $2000. It would be cool as hell to have a carbon frame motorcycle with carbon wheels. But the scale of manufacturing this sort of thing hasn't evolved to make it cost effective, and safety / reliability is definitely more of a concern.

On a bicycle, the advantage of carbon is that it can be made stiff where it needs to be, and more compliant in other areas (for comfort). It can also be thinner where you don't need as much strength, which is where most of the weight savings comes in. In my limited knowledge, motorcycle frames don't need to have compliance built in, and need to be strong pretty much everywhere...so carbon wouldn't have a huge advantage over aluminum except for bling factor (not to be under rated).

Nuts & Volts
01 March 2011, 1115
Ted wants real world numbers I believe (hell thats what I want too). Math does show that weight loss will allow faster acceleration, but by how much in the real world. The thing I see is that less weight allows better handling/cornering. More energy cant do that :)

Good points on carbon Noah. Thanks

teddillard
01 March 2011, 1205
Exactly... and how incremental frame stiffness really translates to handling and lap time. That's something that you'd be hard-pressed to get numbers for, it would be interesting to see what pro riders who've ridden steel say about it.

harlan
01 March 2011, 1311
Come on Ted. We don't need none of that new fangled metal stuff. The Iron Age was overrated. Make mine out of bamboo.

teddillard
01 March 2011, 1323
Funny you should mention that... :D

http://erbacycles.com/wp-content/uploads/2010/10/erban-bamboo-bike-black-build2.jpg

I'm working with these guys to do a hub-drive version. They're right here in Boston...
http://erbacycles.com/

podolefsky
01 March 2011, 1635
Ted wants real world numbers I believe (hell thats what I want too). Math does show that weight loss will allow faster acceleration, but by how much in the real world. The thing I see is that less weight allows better handling/cornering. More energy cant do that :)

Good points on carbon Noah. Thanks

I agree, it's hard to get exact numbers. I'd say that math can give you an upper bound on how much you could save. So say you drop 5% in non-rotating weight - you can figure out the most that could possibly buy you, then decide if it's worth even doing the experiment. You can also figure out whether some claims are total b.s.

Fortunately, straight line acceleration and hill climbing effort are two of the easiest things to calculate...the trouble is with the "all other things being equal" part. Even with real world experiments, that's the biggest problem...all things are almost never equal.

Nuts & Volts
01 March 2011, 1802
I agree, it's hard to get exact numbers. I'd say that math can give you an upper bound on how much you could save. So say you drop 5% in non-rotating weight - you can figure out the most that could possibly buy you, then decide if it's worth even doing the experiment. You can also figure out whether some claims are total b.s.

Fortunately, straight line acceleration and hill climbing effort are two of the easiest things to calculate...the trouble is with the "all other things being equal" part. Even with real world experiments, that's the biggest problem...all things are almost never equal.

Totally agree. I think thou you'll find on El Moto that, yes, most of us will see and believe the calculations and numbers, but so what. We want real world experiences to dictate our decisions. It's really a matter of how accurate or comparable they may be to our personal applications, it's more about the respect we have for actual data collected directly from the road. A lot of people can estimate the numbers and make claims, fewer can actually do it right math right :), even fewer than that can actually build a EV, and then a very small few can provide the real world data to back up the claims they made. At least thats my take! Thats why i love these technical threads because it makes me hope that it will push more people to collect and share the data they have. And eventually it'll motivate me :)

Oh and as for frames. I think a motorcycle made of bamboo would be so cool, I have socks made of bamboo :)

podolefsky
01 March 2011, 1947
Oh and as for frames. I think a motorcycle made of bamboo would be so cool, I have socks made of bamboo :)

I want a motorcycle made out of socks.

DaveAK
01 March 2011, 2020
I want a motorcycle made out of love, that runs on happiness.

And world peace.

Nuts & Volts
01 March 2011, 2111
I want a motorcycle made out of love, that runs on happiness.

And world peace.

Sorry, all we got is socks and electricity

DaveAK
01 March 2011, 2145
Sorry, all we got is socks and electricity
Ah well, that's just as good. :)

__Tango
01 March 2011, 2243
And harsher punishments for parole violators.

teddillard
02 March 2011, 0340
nuff said...

Square Wave
02 March 2011, 0412
I think the hard numbers are available—they’re just difficult to isolate. Racing motorcycles get faster every year as evidenced by dropping lap times. I know that reduced lap times are a product of improvements in every component, but you would have to include frame developments as a factor. The horse power isn’t that much higher and the bikes aren’t any lighter. Most of the speed comes from suspension, frame, and tire improvements. The rule books continually add restrictions to slow the bikes down, because of liability fears regarding the safety of the race tracks, otherwise bikes would be even faster.